Using Photoshop CS5 (not sure about older versions), you put the folders you want to apply the adjustment to in one group, set the group mode to "Normal", and put the adjustment layer on top of all the layers in the group.

In the screenshot below, the color balance layer is only applied to layers 2 and 3, inside Group 1.

You can definitely do what you're after using Clipping Groups. You'll need to ensure the bottom layer is large enough to cover the area required for all the layers above it, because that's what will be used to mask all the layers.

Another option is to create Groups, with a bitmap or vector masks that clips all the layers within the group. This will also keep any adjustment layers to the layers in the group.

Or, as others have suggested, you could just create a mask for the adjustment layer itself. It really depends where you need the flexibility. I don't believe you can limit the adjustment layer's effect to a group without a mask of some kind.

If the IMAGE layers have transparency, i.e. you have erased or masked part of them, you can affect only those layers by Ctrl+Shift clicking their layer icons to select their transparency, then making your adjustment layer. This will automatically mask the adjustment layer to only affect those selected.